The invention relates to a spray-treatment device, in particular to a device for spray-painting of objects comprising a transport means or a support for the objects, and collection means for collecting the excess spray medium passing by the objects and the transport means.
With the application of the spray medium (i.e. spraying of liquid lacquer or powder) on the objects (work piece) the problem arises to remove the spray medium which does not reach the objects while subsequently complying with environmental laws.
It is known to combine the excess spray medium (overspray) with coagulating agents dispersed in water, thus extracting a sediment. The resulting sediment is, of course, hazardous waste, which is problematic and costly to remove. In addition, the water's surface is not arranged in a favorable spatial position for collection and a highly mechanical/technical effort is necessary in order to incorporate this technology.
Furthermore, it is known to send the objects on conveyer belts through an automatic spray-machine to mechanically remove deposited spray-medium excess by scraping or abrasion. This system serves mainly for the purification of the conveyer belt.
The desired collection of the excess spray-medium in conjunction with recycled use is not evident. Moreover, the conveyer belts must be dried after the abrasion before they come in renewed contact with the objects. The speed of the excess spray-medium is pegged to a slow conveyor speed of the objects in the spray machine, whereby a considerable amount of time passes between the spraying of the spray medium and the collection of the excess from the conveyor belts. This leads to increased evaporation of the solution, not only imposing a greater environmental burden, but also hindering collection of the spray-medium on the conveyor belts.
Furthermore, it is also known in DE-OS 28 23 958 to provide a spray-compartment in which the objects are suspended on hooks, in order to form, by means of a rotating belt, a vertical curtain for the preliminary spray medium on the objects, thereupon the deposited spray-medium on the belt is mechanically stripped off the belt.